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M Nishio

Publications and source records attributed to M Nishio.

At least 181 records · Page 10Linked to original sources
PubMed1995

Identification of regions on the hemagglutinin-neuraminidase protein of human parainfluenza virus type 2 important for promoting cell fusion.

The hemagglutinin-neuraminidase (HN) and fusion (F) glycoproteins of two paramyxoviruses, human parainfluenza virus type 2 (PIV2) and simian virus 41 (SV41), were expressed in HeLa cells by transfecting with recombinant plasmid harboring each glycoprotein gene. Expressed F proteins could not induce cell fusion by themselves, but evoked prominent cell fusion when coexpressed with homologous HN proteins. It was also proved that PIV2 HN protein could weakly promote SV41 F-mediated cell fusion. By analyzing the fusion-promoting function of chimeric HN proteins of PIV2 and SV41, it was revealed that the N-terminal region (about 16% of total amino acids) of either PIV2 HN or SV41 HN protein could define the type-specific fusion-promoting function for homologous F protein. Analyses of additional chimeras indicated that the N-terminal region in PIV2 HN protein (designated region I, consisting of 94 amino acids) could be reduced to a 58-amino-acid region (region I') which was located at the membrane-proximal end of the ectodomain. Furthermore, PIV2 HN protein proved to promote cell fusion mediated by PIV4A F protein. Unexpectedly, analyses of another set of chimeras revealed that the promoting function of PIV2 HN protein for PIV4A F-mediated cell fusion was not merely carried by its region I but also by another region ranging from residue 148 to 209 (region II). Finally, it was indicated that regions I' (in the presumed stalk domain) and II (in the globular head) in PIV2 HN protein might play important roles in promoting cell fusion mediated by the F proteins.

Amino Acid Sequence↗
PubMed1995

Molecular characterization of fusion regulatory protein-1 (FRP-1) that induces multinucleated giant cell formation of monocytes and HIV gp160-mediated cell fusion. FRP-1 and 4F2/CD98 are identical molecules.

Fusion regulatory protein (FRP)-1 regulates virus-mediated cell fusion and fusion of monocytes. Eleven of fifteen N-terminal amino acids of FRP-1 were the same as the amino acid sequence of 4F2/CD98 heavy chain. FRP-1 molecules were detected in Con A- or IL-2-stimulated lymphocytes, while FRP-1 was rare on resting lymphocytes. These properties of FRP-1 are similar to those of 4F2/CD98. Treatment of monocytes with anti-4F2/CD98 mAbs resulted in cell fusion, and other mAbs directed against 4F2/CD98 induced formation of multinucleated giant cells of Cd+U2ME-7 cells, a CD4+U937 cell line transfected with the HIV gp160 gene. Both anti-4F2/CD98 and anti-FRP-1 mAbs reacted with murine L929 cells expressing human 4F2/CD98 transiently or constitutively. When Newcastle disease virus (NDV)-infected L929 cells expressing human FRP-1/CD98 were incubated with mAb 4-5-1, an anti-FRP-1 mAb, multinucleated giant cells were induced; thus, FRP-1/CD98 molecules expressed in L929 cells are functional for fusion regulatory activity.

Amino Acid Sequence↗
PubMed1995

Quantitative EEG in never-treated schizophrenic patients.

To clarify whether patients with schizophrenia still show EEG slowing in the absence of psychopharmacological treatment, EEG was analyzed in 20 acute never-treated schizophrenics and 20 age-matched healthy controls using the computerized wave-form recognition method. Compared to controls, schizophrenics had more fast theta (6-8 Hz) and slow alpha (8-9 Hz) activity, and less fast alpha activity (9-13 Hz). The average EEG frequency at O1 correlated negatively with total and positive symptom scores on the BPRS in the schizophrenic group. These findings confirm that the frequency of alpha rhythm is slowed in schizophrenia and that this slowing is possibly related to the expression of psychopathology in this disorder.

Adult↗
PubMed1995

A cell fusion-inhibiting monoclonal antibody binds to the presumed stalk domain of the human parainfluenza type 2 virus hemagglutinin-neuraminidase protein.

Previously, we obtained a neutralizing monoclonal antibody directed against the hemagglutinin-neuraminidase (HN) protein of human parainfluenza type 2 virus (PIV2), which was able to prevent cell fusion without affecting the hemagglutinating and neuraminidase activities. In this study, four escape mutants of PIV2 have been obtained under pressure of the monoclonal antibody. Intriguingly, the HN protein of each mutant proved to have two amino acid substitutions, one of which is at 83Asn or 91Lys, and another one is at 150Leu, 160Ala, or 186Met. One mutant designated F13, which has substitutions at 83Asn and 186Met in the HN protein, could not cause cell fusion in HeLa cells despite its multiple replication, while the other mutants formed typical syncytial cells. The deduced amino acid sequence of F13 fusion (F) protein proved to be identical to that of wild-type F protein, and furthermore, protein expression analyses have revealed that the low-fusion phenotype of F13 was due to its mutated HN protein, whose antigenicity to the monoclonal antibody was abolished by the single mutation at 83Asn. These observations have suggested that the principal epitope for the monoclonal antibody resides in the presumed stalk domain of the HN protein, which may play an important role in promoting cell fusion.

Amino Acid Sequence↗
PubMed1995

Comparison of antiplatelet effects of FK409, a spontaneous nitric oxide releaser, with those of TRK-100, a prostacyclin analogue.

The anti-platelet effects of FK409 ((+/-)-(E)-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexeneamide) , a new spontaneous nitric oxide releaser, and TRK-100 (sodium dl-4-[(1R,2R,3aS,8bS)-1,2,3a,8b-tetra-hydro-2-hydroxy-1-[(3S ,4RS)-3-hydroxy- 4-methyl-oct-6-yen-(E)-1-enyl]-5-cyclopenta[b]benzofuranyl]butyrate), a stable prostacyclin analogue, were studied both in vivo and in vitro. FK409 and TRK-100 inhibited ADP-induced platelet aggregation in rat platelet-rich plasma at 1.0 and 0.032 microM, respectively. In a rat extracorporeal shunt model, FK409 suppressed thrombus formation dose dependently and significantly at 1.0 mg/kg and showed the maximum inhibition (52% inhibition) at 10 mg/kg. TRK-100 showed 79% inhibition of thrombus formation at 1.0 mg/kg, but not at less than 1.0 mg/kg. At the doses required for antiplatelet effects, TRK-100 decreased mean blood pressure significantly but FK409 did not alter the blood pressure. These data suggest that FK409 shows more selective activities on platelets than TRK-100 in these experiments.

Adenosine Diphosphate↗
PubMed1995

High-resolution solution structure of siamycin II: novel amphipathic character of a 21-residue peptide that inhibits HIV fusion.

The 21-amino acid peptides siamycin II (BMY-29303) and siamycin I (BMY-29304), derived from Streptomyces strains AA3891 and AA6532, respectively, have been found to inhibit HIV-1 fusion and viral replication in cell culture. The primary sequence of siamycin II is CLGIGSCNDFAGCGYAIVCFW. Siamycin I differs by only one amino acid; it has a valine residue at position 4. In both peptides, disulfide bonds link Cys1 with Cys13 and Cys7 with Cys19, and the side chain of Asp9 forms an amide bond with the N-terminus. Siamycin II, when dissolved in a 50:50 mixture of DMSO and H2O, yields NOESY spectra with exceptional numbers of cross peaks for a peptide of this size. We have used 335 NOE distance constraints and 13 dihedral angle constraints to generate an ensemble of 30 siamycin II structures; these have average backbone atom and all heavy atom rmsd values to the mean coordinates of 0.24 and 0.52 A, respectively. The peptide displays an unusual wedge-shaped structure, with one face being predominantly hydrophobic and the other being predominantly hydrophilic. Chemical shift and NOE data show that the siamycin I structure is essentially identical to siamycin II. These peptides may act by preventing oligomerization of the HIV transmembrane glycoprotein gp41, or by interfering with interactions between gp41 and the envelope glycoprotein gp120, the cell membrane or membrane-bound proteins [Frèchet, D. et al. (1994) Biochemistry, 33, 42-50]. The amphipathic nature of siamycin II and siamycin I suggests that a polar (or apolar) site on the target protein may be masked by the apolar (or polar) face of the peptide upon peptide/protein complexation.

Amino Acid Sequence↗
PubMed1995

FK409, a new nitric-oxide donor, suppresses smooth muscle proliferation in the rat model of balloon angioplasty.

The effect of FK409, a new nitric-oxide (NO) donor, on neointimal formation of rat carotid arteries following balloon injury was studied. The intimal thickening at 14 days was strongly suppressed by twice daily administration of FK409 at 10 mg/kg from 2 days before to 13 days after injury. The neointima area and neointima/media ratio were decreased by 48.0% (P < 0.01) and 38.5% (P < 0.01), respectively, compared with control. On the other hand, isosorbide dinitrate (ISDN), a classical nitro-vasodilator, did not suppress intimal thickening even at 100 mg/kg twice a day. An in vivo 5-bromo-2'-dedoxyuridine (BrdU) uptake study revealed that FK409 inhibited the proliferative response of smooth muscle cells (SMC) in media at early stage of injury. In fact, the neointimal formation at 14 days was inhibited by the short term administration of FK409 only from the day of injury to 4 days after at 10 mg/kg twice a day. In cultured rat SMC, FK409 (1-10 mumol/l) markedly enhanced intracellular c-GMP and inhibited the proliferation in 10% FBS-containing medium. These results suggest that FK409 suppresses intimal thickening following balloon injury of the rat carotid artery by inhibition of SMC proliferation.

Angioplasty, Balloon↗
PubMed1995

L-type Ca channel block by highly hydrophilic dihydropyridines in single ventricular cells of guinea-pig hearts.

Blocking of L-type Ca channels by highly hydrophilic dihydropyridines, NKY-722 and KV-1360, was investigated in single ventricular cells of guinea-pig hearts using the whole-cell voltage clamp technique. At a holding potential of -30 mV, NKY-722 (1-100 nM) decreased the amplitude of the L-type Ca channel current (ICa) in a concentration-dependent manner. NKY-722 did not change the time constants of the decay of ICa. In the presence of NKY-722 (1 microM), the steady-state inactivation curve was shifted toward a more negative potential (by -33.0 +/- 2.0 mV) without changing its slope factor. The use-dependent block was elicited at a pulse frequency of 3.3 Hz or more. Even after washing out the drug at -80 mV for 20 min, ICa inhibited by NKY-722 (100 nM) at -30 mV was scarcely recovered when the membrane potential was clamped back to -30 mV. A permanently charged compound KV-1360 (0.1-1 microM), a quaternary amine derivative of NKY-722, hardly affected ICa by intracellular and extracellular application. These results suggest that, in spite of the high degree of ionization (91% in the charged form at pH 7.4), the mode of the L-type Ca channel block by NKY-722 is quite similar to that by lipophilic dihydropyridines. Consequently, the neutral form of NKY-722 is the active compound and this reaches the dihydropyridine receptor by "membranous approach".

Animals↗
PubMed1995

Sequence analyses of human parainfluenza virus type 4A and type 4B fusion proteins.

cDNAs encoding human parainfluenza virus type 4A and type 4B (hPIV-4A and -4B) fusion (F) proteins were cloned and sequenced. The predicted amino acid sequences of the F proteins had similar characteristic traits to those reported for the F proteins of other paramyxoviruses. They were more closely related to the F proteins of simian virus 5 (SV5), mumps virus (MuV), hPIV-2 and Newcastle disease virus (NDV) than to the F proteins of hPIV-1, hPIV-3, Sendai virus (SV) and measles virus (MV). In addition, hPIV-4A, hPIV-4B, SV5 and MuV shared a common feature of genomic organization: there was a small ORF between the F and haemagglutinin-neuraminidase (HN)-coding sequences, implying a common ancestry.

Amino Acid Sequence↗
PubMed1995

Superficial esophageal cancer: multicenter analysis of results of definitive radiation therapy in Japan.

PURPOSE: To assess the effectiveness of definitive radiation therapy in patients with superficial esophageal cancer. MATERIALS AND METHODS: Method of irradiation, local control rate, survival rate, and complications were assessed in 105 patients (89 men, 16 women; age range, 50-88 years) with superficial esophageal cancer treated with definitive radiation therapy at 15 hospitals in 1981-1990. RESULTS: All lesions were confirmed to be squamous cell carcinoma. The overall 5-year survival rate was 38.7%; the 5-year disease-specific survival rate was 71.0%. The 2-year local control rate was 83.0%. Late complications occurred in 16 patients. The prevalence of complications was relatively high in the group treated with intraluminal radiation therapy. CONCLUSION: Local control and survival rates in patients treated with radiation therapy were excellent, especially in the group treated with external and intraluminal radiation therapy; however, the optimal dose and optimal combination of external and intraluminal radiation therapy should be further assessed.

Aged↗
PubMed1995

Identification of fusion regulatory protein (FRP)-1/4F2 related molecules: cytoskeletal proteins are associated with FRP-1 molecules that regulate multinucleated giant cell formation of monocytes and HIV-induced cell fusion.

Fusion regulatory proteins (FRPs) regulate virus-mediated cell fusion and multinucleated giant cell formation of monocytes. Anti-FRP-1 mAbs immunoprecipitated 80 kDa and 38 kDa proteins from HeLa cells. After long exposure other bands were detected, suggesting the presence of molecule(s) associated with FRP-1. To identify the molecule(s), we prepared monoclonal antibodies against immunoaffinity-purified FRP-1 complex derived from membrane fractions of HeLa cells. Immunofluorescence microscopy revealed that these monoclonal antibodies recognized the intracytoplasmic molecules in HeLa cells. Using immunoblotting, the antibodies reacted with 200 kDa, 70 kDa, 55 kDa and 35 kDa molecules, so we designated these molecules as FRP-related molecules (FRMs). Subsequently, we performed gene cloning from a HeLa lambda gt11 cDNA library using anti-FRM mAbs and immunoblotting analysis with either purified cytoskeletal proteins or specific antibodies against various cytoskeletal proteins. Three kinds of positive clone were obtained, which encoded partial sequences of vimentin, tropomyosin, and heat shock cognate protein 70 (hsc70). The 200 kDa molecule was expected to be a myosin heavy chain, judging from the immunoblotting pattern. Immunoblotting confirmed that these purified proteins were readily recognized by anti-FRM mAbs. Furthermore, anti-vimentin and anti-myosin mAbs reacted with the precipitates by anti-FRP-1 mAb, indicating a physical association between FRP-1 molecules and these cytoskeletal proteins. When anti-FRP-1 mAb was added to culture fluids of HeLa cells, the cell-shape and immunofluorescence-pattern stained with anti-FRM mAbs changed. Taken together, the fusion regulatory molecular complex is suggested to consist of at least FRP-1, hsc70, actomyosin and vimentin systems.

Antibodies, Monoclonal↗
PubMed1994

Complete Nucleotide Sequence of Mouse Mammary Tumor Virus from JYG Chinese Wild Mice: Absence of Bacterial Insertion Sequences in the Cloned Viral gag Gene.

Mammary tumors of a newly isolated strain of Chinese wild mouse (JYG mouse) harbor exogenous mouse mammary tumor virus (MMTV). The complete nucleotide sequence of exogenous JYG-MMTV was determined on the proviral 5' long terminal repeat (LTR)(partial)-gag-pol-env-3' LTR (partial) fragment cloned into a plasmid vector and the cDNA sequence from JYG-MMTV producing cells. Similarly to the other MMTV species the LTR of JYG-MMTV contains an open reading frame (ORF). The amino acid sequence of the JYG-MMTV ORF resembles that of SW-MMTV (92% identity) and endogenous Mtv-7 (93% identity) especially at the C-terminal region. Thus, a functional similarity in T-cell receptor V beta recognition as a superantigen is implicated among these MMTV species. Analysis of the viral gag nucleotide sequence revealed that this gene is not disrupted by the bacterial insertion sequence IS1 or IS2, which have been reported to be present in the majority of the plasmids containing the gag region. Comparison of amino acid sequences of JYG-MMTV with those of BR6-MMTV showed that over 96% of the amino acids of gag, pol, protease and env products are identical. These results suggest the intact nature of the nucleotide sequence of the near full-length MMTV genome cloned in the plasmid.

Journal Article↗
PubMed1994

Expression of fusion regulatory proteins (FRPs) on human peripheral blood monocytes. Induction of homotypic cell aggregation and formation of multinucleated giant cells by anti-FRP-1 monoclonal antibodies.

Fusion regulatory proteins (FRPs) are newly defined cell surface molecules that enhance and/or induce virus-mediated cell fusion. Anti-FRP-1 Abs reacted with all of the established cells derived from humans and monkeys, whereas FRPs were found to be selectively expressed on a fraction of monocytes in human PBMCs. Granulocytes expressed no FRP-1 molecules, but approximately 18% of granulocytes expressed FRP-2 molecules. Alveolar macrophages also expressed FRP-1 molecules. FRP-1 expression was enhanced by culture of monocytes, but CD14 expression was not influenced by cultivation. Anti-FRP-1 Abs induced homotypic cell aggregation and multinucleated giant cell formation of monocytes. Anti-beta 2 integrin Ab blocked anti-FRP-1 Ab-induced cell aggregation, and anti-beta 1 integrin Ab and fibronectin inhibited anti-FRP-1 Ab-induced polykaryocyte formation. There was no competitive binding to monocytes between anti-FRP-1 Ab and anti-beta 1 or anti-beta 2 integrin Ab or fibronectin. Furthermore, there was no enhancement of beta 1 and beta 2 integrin expression by anti-FRP-1 Ab on monocytes. These findings suggest that anti-FRP-1 Ab activated integrin systems, and that the functions of anti-FRP-1 Ab were demonstrated through the activated integrin systems. Furthermore, it is inferred that integrin systems are involved in polykaryocyte formation of monocytes.

Amino Acid Sequence↗